Splicing of Timber Piles

Timber piles need to be installed with special care. They are susceptible to brooming and damage. Any sudden decrease in driving resistance should be investigated. Splicing of timber Piles, if required, should comply following requirements:

2. The usual practice is to provide a pipe section (known as a sleeve) and bolt it to two piles.

Splicing
of timber piles. (a) Usually, timber piles are tapered prior to
splicing as shown here. (b) The sleeve (or the pipe section) is
inserted. (c) The bottom pile is inserted. (d) The pipe section is
bolted to two piles.

3. Sleeve joints are appro-ximately 3 to 4 ft in length. As one can easily see, the bending strength of the joint is much lower than the pile. Splice strength can be increased by increasing the length of the sleeve.

4. Most building codes require that no splicing be conducted on the upper 10 ft of the pile since the pile is subjected to high bending stresses at upper levels.

Precautions:

1. Sleeves larger than the pile may get torn and damaged during driving and should be avoided. If this type of sleeve is to be used, the engineer should be certain that the pile sleeve is not driven through hard strata.

Concrete–timber composite pile

2. Timber splices are extremely vulnerable to uplift (tensile) forces and should be avoided. Other than sleeves, steel bars and straps are also used for splicing.